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Full text of "IS 14164: Industrial application and finishing of thermal insulation materials at temperature above -80 deg C and up to 750 deg C - Code of practice"

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IS 14164 (2008) : Industrial application and finishing of 
thermal insulation materials at temperature above -80 deg C 
and up to 750 deg C - Code of practice [CHD 27: Thermal 
Insulation] 



Satyanarayan Gangaram Pitroda 
Invent a New India Using Knowledge 




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IS 14164: 2008 

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Indian Standard 

INDUSTRIAL APPLICATION AND FINISHINGS 

OF THERMAL INSULATION MATERIALS 

AT TEMPERATURES ABOVE -80°C AND 

UP TO 750°C — CODE OF PRACTICE 

( First Revision ) 



ICS 27.220 



© BIS 2008 

BUREAU OF INDIAN STANDARDS 

MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG 
NEW DELHI 11 0002 



May 2008 Price Group 12 



Thermal Insulation Sectional Committee, CHD 27 



FOREWORD 

This Indian Standard (First Revision) was adopted by the Bureau of Indian Standards, after the draft finalized by 
the Thermal Insulation Sectional Committee had been approved by the Chemical Division Council. 

This standard was first published in 1994 superseding both IS 7240 : 1981 and IS 7413 : 1981 which were in 
force earlier hoping that the amalgamated standard would facilitate unambiguous exchange of commercial and 
scientific information within the Industry. While formulating this standard considerable assistance was taken 
from VDI 2055 : 1982 'Heating and cooling protection/shielding for factories', published by Verein Deutscher 
Ingenieure', ISO/DIS 12241 : 1993 'Calculations rules for thermal insulation of pipes, ducts and equipments' 
published by International Organization for Standardization, and BS 5422 : 1990 'Method for specifying thermal 
insulating materials on pipes duct work and equipments (in the temperature range -40° to 750°C)'. This standard 
covers the insulation of plant and equipment containing fluids at temperatures above -80°C and up to 750°C. 

This standard does not deal with the insulation of buildings, land or marine cold stores or other cold storages. 
This standard also does not deal with the insulation of metal surfaces, which are protected on their inner surface, 
with refractory brickwork or other refractory linings, the temperatures of which change, with the application of 
external insulation. Thus, this standard covers external insulation of surfaces such as vessels or piping carrying 
hot or cold fluids including gases, at temperatures within the range indicated. 

This standard also does not include calculations for thickness of insulation application as the determination of 
the required thickness of insulation is likely to be governed by many considerations and factors other than 
economics alone. Further, other similar theoretical calculations, such as interface temperatures in multi-layer 
insulations, specified temperature on the surface of the insulation, determination of temperature at the point of 
delivery, thickness required to prevent condensation on the surface of the insulation, etc have also not been 
included in this standard. 

Accordingly the symbol used in thermal insulation, determination of heat gain/heat loss, surface temperature and 
insulation coefficient for different surfaces for working out appropriate surface temperature and insulation thickness 
for specific surface temperatures, additional heat losses due to components in a pipeline, etc and conversion 
factors have been included in this standard in Annexes A, B and C. 

The Committee felt a need for its revision based on the experience gained and feedbacks received from the 
various segments of the thermal insulation trade and industry and also to harmonize with BS 5970 : 2001 'Code 
of practice for thermal insulation of pipe work and equipment in the temperature range of 100°C to 870°C. 
There is no ISO Standard on this subject. During this revision assistance has also been derived from ASTM C 680 
and also from Thermal Insulation Handbook by William C. Turner and John F. Malloy (1981). 

In this revision calculation for heat loss/gain through the insulation, attachments, thickness of metal cladding 
have been incorporated. Typical exemplification figures both for equipment and piping are also incorporated for 
better understanding. Major modifications have been done in the application and measurement clauses. This 
standard takes care of the health hazard of the asbestos fibre and hence incorporates the requirement of asbestos- 
free insulation materials. 

The composition of the Committee responsible for the formulation of this standard is given at Annex D. 

In reporting the results of a test or analysis made in accordance with this standard, if the final value, observed or 
calculated, is to be rounded off, it shall be done in accordance with IS 2 : 1960 'Rules for rounding off numerical 
values (revised) '. 



AMENDMENT NO. 1 DECEMBER 2011 

TO 

IS 14164 : 2008 INDUSTRIAL APPLICATION AND FINISHINGS OF THERMAL 

INSULATION MATERIALS AT TEMPERATURES ABOVE - 80C AND UP TO 

750C — CODE OF PRACTICE 

( First Revision ) 

(Page 26, Table 2, col 9, line 3) — Insert '1.32' for '1.12'. 



(CHD 27) 



Reprography Unit, BIS, New Delhi, India 



IS 14164 : 2008 



Indian Standard 

INDUSTRIAL APPLICATION AND FINISHINGS 

OF THERMAL INSULATION MATERIALS 

AT TEMPERATURES ABOVE -80°C AND 

UP TO 750°C — CODE OF PRACTICE 

( First Revision ) 



1 SCOPE 

1.1 This Code of practice prescribes for application 
and finishing of thermal insulation materials applied 
to surfaces at temperatures above -80°C and up to 

750°C. 

1.2 In cases where metal surfaces are protected on their 
inner faces with structural boundary materials, such 
as refractory brickwork or other linings, the 
temperatures of which change as result of the 
application of external thermal insulation, consequently 
change in metal temperature shall be checked against 
safe design temperature limits. 

2 REFERENCES 

The following standards contain provisions which 
through reference in this text, constitute provisions of 
this standard. At the time of publication, the editions 
indicated were valid. All standards are subject to 
revision, and parties to agreements based on this 
standard are encouraged to investigate the possibility 
of applying the most recent editions of the standards 
indicated below: 

Title 

Industrial bitumen {second revision) 
Bitumen felts for water-proofing and 
damp-proofing {fourth revision) 
Glossary of terms, symbol and units 
relating to thermal insulation 
materials 

Thermal insulation finishing cements 
(first revision) 

3 TERMINOLOGY 

For the purpose of this standard, the definitions given in 
IS 3069 and the following shall apply. Additional 
symbols used in this standard are described in Annex A. 

3.1 Applicator — An individual or organization 
undertaking thermal insulation of the installations. 

3.2 Operating Temperature — The temperature of 
the hot or cold fluid inside the pipe or vessel under 
consideration. 



IS No. 


702: 


1988 


1322 


: 1993 


3069 


: 1994 


9743 


: 1990 



3.3 Effective Ambient Temperature — For structures 
surrounded by air (or other fluid), the effective ambient 
temperature is a suitably weighted mean between air 
(fluid) temperature and the mean radiant temperature 
of the surroundings (°K/°C). For a fluid opaque to 
radiation, the effective ambient temperature is the same 
as the surrounding fluid temperature. For operational 
feasibility of field assessments of the exposed surface 
temperature of insulated system, the effective ambient 
temperature shall be considered as the temperature 
measured by a sensor located normally at a distance 
of 1 m from the surface at which the temperature is 
measured. This is not to be mistaken for the 
atmospheric temperature. 

3.4 Economic Thickness — The thickness of 
insulation, which gives a minimum total cost over a 
chosen evaluation period. 

3.5 Preformed Insulating Material — Thermal 
insulating material which is fabricated in such a 
manner that at least one surface conforms to the shape 
of the surface to be covered and which will maintain 
its shape without cracking, breaking, crushing or 
permanent deformation during handling and 
application. 

3.6 Flexible Insulating Material — Thermal 
insulating material in loose dry or formed matts/slabs/ 
batts/mattresses, which tends to drape or conform to 
the shape of the surface on which it is applied. 

3.7 Plastic Composition Insulating Materials — 

Thermal insulating materials in loose dry form, which 
are prepared for application as a paste or dough by 
mixing with water, usually on site. The normal variety 
sets under the influence of heat applied to the internal 
surface. 

3.8 Microporous Insulation — A family of inorganic 
products of very low thermal conductivity featuring 
silica fibrous matrix with opacifying powders 
distributed throughout the silica structure to reflect, 
refract or absorb infrared radiation resulting in a flat 
conductivity versus Temperature profile. 



IS 14164 : 2008 



3.9 Reflective Insulation — An insulation system 
composed of closely spaced sheets/foils of high 
reflectivity (low emittance) obtaining its insulating 
value from the ability of the surfaces to reflect a large 
part of radiant energy incident on them. This 
arrangement may or may not be evacuated. 

3.10 Thickness — The thickness of the insulation 
material only that is, excluding any protective or other 
finish. 

3.11 Hot Surfaces for Insulation — For the purpose 
of this standard, surfaces to be insulated having a 
temperature over 40°C and where heat flux is expected 
to be away from the surfaces are classified as hot 
surfaces. 

3.12 Cold Surfaces for Insulation — For the 

purpose of this standard, surfaces having a 

temperature of 40°C and below and where the heat 
flux is expected to be towards the surfaces to be 
insulated are classified as cold surfaces. 

4 MATERIALS 

4.1 The materials used for insulation and its application 
shall conform to the relevant Indian Standards, 
wherever they exist. 

4.2 Asbestos — Free Thermal Insulating Material 

All thermal insulation materials used at site shall be 
asbestos-free in order to safeguard the health of 
individuals who are working in the vicinity. 

4.3 Types of Insulating Materials 

Although all thermal insulating materials, with the 
exception of reflective insulation, depend on entrapped 
air or gas for their effectiveness, it is convenient to 
classify them according to their type of structure or 
method of application: 

a) Preformed — Normally the term is applied 
to slabs, pipe sections and related shapes 
based on cellular granules or mineral fibres 
that are bonded to form a substantially rigid 
cellular plastic, cellular glass and bonded 
natural materials, for example, cork and 
exfoliated minerals. 

b) Flexible — This type includes fibrous 
products such as felts, blankets, mats and 
mattresses, which differ from the preformed 
materials only in the ease with which they can 
be shaped to conform to irregular surfaces. 
Textile products, for example, woven cloth, 
tapes, twisted yarns, and plaited packings are 
also of this type. This also includes flexible 
closed cell foams of plastic and specialized 
rubber formulations. 



c) Loose Fill — Included in this type are all 
granular, fibrous and various discrete 
aggregates that can be poured or lightly 
packed into cavities, casings or jackets. Loose 
or lightly bonded fibrous materials, shredded 
plastics polymers and loose expanded 
volcanic or micaceous products, for example, 
perlite or vermiculite, as well as such 
insulating aggregates as foamed slag and 
granulated diatomaceous brick would also fall 
under this heading. 

d) Plastic Composition — Material of this type 
consists of insulating aggregate, with or 
without fibrous reinforcement that is prepared 
for application as a paste or dough by mixing 
with water. Normally the wet materials require 
the use of heat for drying out after application, 
but some products harden by hydraulic 
setting, it is important to distinguish between 
plastic compositions and organic plastics, the 
latter are spelt with water a letter V at the 
end of the word 'plastic'. 

e) Spray — Granular, foamed or fibrous material 
that adheres to the surface on application by 
means of a spray-gun. An adhesive may be 
included in the original mix or it may be 
applied through a separate nozzle during the 
application process. 

f) Foamed-in-situ — Normally cellular organic 
plastics agglomerates that are foamed in a 
cavity by physical or chemical means during 
or immediately after application. 

g) Microporous Insulation (Silica Aerogel) — 
Opacified fine powder having microscopic 
pores that confer particularly low thermal 
conductivity properties, lower than those of 
still air at the same temperatures. It is available 
as block encapsulated in metal foil or woven 
fabric. 

h) Reflective Insulation — Multiple layer of foil 
or thin sheet material of low emissivity that 
has the ability to reflect incident radiant heat 
separated by fleece or tissue. Metal foils such 
as aluminium foil and thin polished stainless 
steel sheet with mineral fiber tissue are 
common examples, but reflective metal 
deposited on plastics film will also be included 
but for lower temperatures only. These 
materials are normally used in association 
with one or more air spaces, which may be 
closed or open and which may or may not be 
evacuated. 

j) Insulating Boards — Rigid or mainly rigid 
boards, often with fibrous reinforcement, 
bonded into a compact mass and baked. The 



IS 14164 : 2008 



bonding material may be a hydraulic cement, 

a lime-silica reaction product, gypsum, or an 

organic plastic polymer. 

k) Prefabricated Shapes — For specialized types 

of application it may be advantageous to 

fabricate the insulation to predetermined 

shapes for ease of application and removal. 

Various types of insulating material can be 

used for this purpose, as also can various types 

of covering material. Typical products would 

be prefabricated valve covers, insulated metal 

valve boxes, prefabricated flexible mattresses 

and thin layers of fibrous or granular filling 

sealed inside prefabricated metal-foil 

envelopes. 

4.4 The applicator shall ensure that the thermal 
insulating and finishing materials used are suitable for 
service at the operating temperatures and under the 
physical conditions stated by the purchaser, in case the 
material is supplied by the applicator. In case the 
purchaser or any other agency appointed by the 
purchaser specifies or supplies the material, the 
responsibility for the performance of such materials 
shall rest with the purchaser or the supplier, as the case 
may be, and the applicator of such materials shall rest 
with the purchaser or the supplier, as the case may be, 
and the applicator shall be responsible only for the 
workmanship. If the material supplied conforms to the 
relevant Indian Standard, the applicator's responsibility 
shall then be confined to the methods of application as 
stated in this Code, unless otherwise specifically agreed 
to between the purchaser and the applicator. 

4.5 In the case of plants operating at dual temperatures, 
that is, below and above ambient temperature, such as 
cold insulated systems which are periodically steam 
cleaned, the insulation material used shall be capable 
of withstanding the highest and lowest temperature 
involved during services without physical deformation 
or deterioration. In all such cases extreme care is 
required in selection of insulants, vapour barriers and 
their positioning in the system and proper study of the 
interface temperature between layers. 

5 METHODS OF APPLICATION 

5.1 General 

5.1.1 All insulation materials, fixed in any manner 
should be applied so as to be in close contact with the 
surface to which they are applied and the edges or ends 
of suctions shall butt up close to one another over their 
whole surface except in special application. For this 
reason edges or ends shall, where necessary, be cut or 
shaped at site. 

5.1.2 While applying flexible materials care shall be 



taken to ensure that the material is applied at the 
required density. 

5.1.3 While applying multi-layer insulation all joints 
shall be staggered; and each layer shall be separately 
secured to the surface. 

5.1.4 As a rule fittings on vessels shall be covered with 
an independent insulation so as to allow easy access 
and removal without disturbing the main insulation. 

5.2 Insulation on Ambient and Hot Surfaces 

5.2.1 Guidelines for Normal Ambient and Elevated 
Temperatures 

As there is possibility of differential movement of 
jointly insulated pipe lines due to differences in the 
temperature of the fluids carried by the pipe lines, each 
pipe line is to be insulated separately, wherever space 
is available. 

5.2.1.1 When the surface to be insulated is of regular 
shape it is likely that preformed materials will be the 
most suitable; their physical properties, shapes and 
dimensions can be controlled during works 
manufacture. Also, they are easy to apply and they are 
likely to retain their physical characteristics under 
service conditions. Care should be taken to ensure that 
the material stays satisfactorily in service, and this will 
include the need to preserve physical and mechanical 
integrity as well in order to maintain thermal 
effectiveness. 

5.2.1.2 Certain types of plant with double-skin 
construction, that is reaction or storage vessels, may 
require the annular space to be packed with a loose 
mass of fibre or a porous granular aggregate. In such 
cases, it is necessary to achieve reasonably uniform 
packing at an optimum bulk density, for example, by 
the provision of internal spacer supports to prevent 
settlement under service conditions. 

For some specific applications, notably the horizontal 
or near-horizontal tops of large outdoor ducts and flues 
with multiple external stiffeners, it may be convenient 
to build up an appreciable depth of granular aggregate 
to form a camber, either from the longitudinal center 
line outwards or across the full width of the surface, 
before applying preformed slab insulation, which may 
be finished with a layer of self-setting cement. A final 
coat of weatherproofing compound may be added, as 
required. 

5.2.1.3 For irregular shapes of plant it may be 
convenient to make use of plastic composition 
insulating materials but in these cases, it will be 
necessary to preheat the plant and to maintain the heat 
until all the insulation is dry. Wet plastic composition 
has to be applied in successive layers, allowing each 



IS 14164 : 2008 



one to dry before the next is applied. Plastic 
composition mixes are likely to contain soluble 
chloride salts, either as normal impurities or in the water 
used for forming the paste, which may cause or 
accelerate stress-corrosion attack on austenitic steel 
surfaces. Additionally, only potable water should be 
used for mixing in order to ensure freedom from attack 
on carbon steel surfaces by soluble nitrates. 

5.2.1.4 Notably low thermal-conductivity values, 
together with light weight, are characteristic of many 
types of foamed-in-situ insulating materials, which 
normally involve the mixing of two reactive chemicals, 
for example, for the production of polyurethane. They 
are of particular value for filling the annular spaces 
between the containment surfaces of a light weight 
structure as, in many cases, they can increase the 
mechanical stability of the structure. It is possible to 
use a similar process for the production of preformed 
insulating shapes. Care should be taken to ensure that 
the foamed material is used only within the correct 
temperature range and that it does not add to the fire 
hazard in the insulated plant. 

5.2.1.5 Microporous insulation is characterized by its 
low thermal conductivity, which persists to high 
temperatures. This characteristic permits the use of 
lower thickness than those of conventional materials. 
It is important that microporous insulation should never 
become wet as this can result in an irreversible 
breakdown of the microporous structure. 

5.2.1.6 Reflective insulation is more effective in 
reducing the absorption or emission of radiant heat than 
in a non-metallic surface. It may be used in conjunction 
with granular, fibrous, or powder-type insulating 
materials, and insulation purposes. Where the use of 
non-metallic insulation is not acceptable for technical 
reasons, for example, in certain types of plant heated 
by nuclear fuels, multilayer reflective metallic 
insulation may be particularly suitable. 

5.2.1.7 Insulating boards may be substantially of 
organic composition, for example, made from wood 
fibre, sugarcane etc, or they may be wholly inorganic, 
for example, mineral fibres bonded with a cement- 
type product. Included in this range are gypsum 
plasterboard and sheet products made from rigid 
organic polymer foam, both of which may have one 
or both surfaces covered with aluminium foil to 
reduce thermal transmission. When a choice is to be 
made from various types of board for a specific 
application, attention should be paid to fire hazard, 
moisture absorption, and the upper limiting 
temperature, as well as to the thermal conductivity 
under the required conditions of use. 

5.2.1.8 At high temperature (above 500°C) with the 
combination of back-up material. Ceramic fibre may 



be used in applications where low thermal mass and 
high resistance to thermal shock are important. 

5.2.1.9 It may be convenient to use two different types 
of insulating material for a portion of plant if the 
operating temperature is above the limiting temperature 
for the preferred main insulating material. In such cases 
the inner layer, of suitable resistance for the higher 
temperature is used in sufficient thickness to reduce 
the temperature at the interface with the main insulating 
material to an acceptable level. 

5.2.2 Application System for Hot Insulation 

5.2.2.1 Pipes 

Preformed pipe sections should be fitted closely to the 
pipe and any unavoidable gaps in circumferential or 
longitudinal joints should be filled with compatible 
insulating material where the pipe diameter is too large 
by building up the radius and bevelled piping. Where 
there is more than one layer of insulating material, all 
joints should be staggered. 

Each section should be held in position and covered 
by a fabric, this should be secured by stitching or by 
the use of an adhesive. The edges of the fabric, if 
stitched should overlap by at least 25 mm. Alternatively, 
with a fabric or sheet outer finish, the whole may be 
secured by circumferential bands. 

For vertical and near vertical piping it is important to 
prevent downward displacement of the insulating 
material by the use of appropriate supports, which may 
be in the form of metal rings, part rings, or studs. These 
supports should be located at intervals of not more than 
5.0 m and in any case, there should be a support 
immediately above each expansion break in the 
insulation. 

5.2.2.2 Piping bends 

Bends are usually insulated to the same specification 
as the adjacent straight piping. Where preformed 
material is used it should be cut in mitred segment 
fashion and wired or staggered into position. 
Alternatively, prefabricated or fully moulded half- 
bends may be used, if these are available. Plastic 
composition may be used to seal any gaps that may 
appear between mitred segments. 

5.2.2.3 Flanges, valves and other fittings on hot piping 

It is essential that valves and flanges be insulated along 
with the piping. 

Valve and flange boxes are lined with preformed rigid 
or flexible insulating material. Direct contact between 
the metal of the box and the insulated metal surface 
should be avoided. This can be insulated by mattresses 
which consist of glass or silica fibre cloth envelope 
packed with loose fill. 



IS 14164 : 2008 



5.2.2.4 Flexible insulation 

Where flexible insulation (for example, mattresses) are 
used for insulation of pipes, it is necessary to 
understand that a flat product is to be wrapped around 
a curved profile of a pipe where there is considerable 
difference in the inner and outer perimeters of the 
applied insulation. It is therefore essential to size the 
mattress of a specified width with a length equal to the 
outer perimeter to ensure that the blanket material 
provides a total thermal envelope. It is also necessary 
to limit the thickness of individual layers of insulation 
for a distortion-free condition of the insulant. Further, 
a flexible matrix may not have the required compressive 
strength to bear the external load, including the weight 
of the outer covering. Cladding support rings, fitted 
with spacers (equal to thickness of insulation) would 
be required for the purpose. 

5.2.2.5 Plastic composition 

Before application of plastic composition, the pipe 
surface should be heated to a minimum temperature 
of 65°C. The composition should be applied by hand 
in layers, each layer being allowed to dry before 
successive layers are applied. The first layer should be 
limited to 12 to 25 mm in thickness. Remaining layers 
may be built up of 25 mm thickness. 

5.2.2.6 Spray insulation 

Spray applied insulation is generally suitable for 
irregular surfaces where it is applied on pipes suitable 
for diameter greater than 150 mm nominal size and 
good all round access is necessary. Adjacent equipment 
should be protected from overspray. Mineral fibres and 
polyurethane foam can be applied by spraying. 
Workshop spraying should be carried out in suitable 
booth and the operator should wear protective clothing, 
including a fresh-air mask. 

5.2.2.7 Loose fill insulation 

Loose-fill will require an outer retaining cover fitted 
to the pipe with necessary spacers and the filling should 
be poured or packed to the density as called for to meet 
required thermal conductivity. In vertical pipes, baffle 
plates should be fitted as necessary to prevent settling. 

5.2.2.8 Vessels and large surface 

Generally the need to dismantle associate pipe work 
for inspection should be anticipated and permanent 
insulation ended sufficiently far from flanges to enable 
bolts to be withdrawn. 

5.2.2.9 Preformed materials 

It may be necessary to cut preformed materials to fit 
any irregular contour. Alternatively, suitable material 
may be applied to render the surface close to a regular 



shape as a foundation layer. All cut faces should be 
clean and care should be taken to butt adjacent edges 
closely. 

5.2.2.10 Flexible material 

Adjacent edges of flexible insulation should be secured 
in close contact with each other by binding together 
outer containing medium such as a wire netting. Care 
should be taken to see that air spaces are kept to a 
minimum and that there are no free passages from hot 
surfaces to atmosphere. 

5.2.2.11 Spray insulation 

The material consists of a mixture of milled mineral 
fibre and hydraulic binders. It is applied by spraying 
together with jets of deionized water. 

5.2.3 Where protrusions are such that they are also 
insulated (like pipe-connections) but with an insulation 
thickness less than that of the main system, full 
thickness of the main system is to be extended along 
such extensions for a length of not less than thrice the 
full thickness. 

5.3 Insulation Over Cold Surfaces 

5.3.1 For an equal temperature difference across the 
insulation, the thickness of same material required for 
cold insulation is relatively higher than for hot 
insulation. Since the vapour seals applied to the 
insulated cold surfaces are frequently trowelled or 
sprayed-on, it is essential that the purchaser gives 
consideration, at the design stage, to the sealing to be 
used, to ensure that there is sufficient working space 
between pipes, vessels and structures to allow easy 
application of all the materials involved. 

5.3.2 Special care should be taken over the application 
and vapour-sealing of cold insulation, since even 
minute faults can lead to condensation taking place 
within the insulation or to ice formation on the cold 
surface. 

5.3.3 Even though there is less possibility of movement 
of pipes having cold surfaces, it is preferable to insulate 
the pipes separately as far as possible. 

5.3.4 Where multilayer insulation is adopted on cold 
surfaces, in addition to the precautions given in 5.3.1, 
the final two layers shall be provided with adequate 
vapor barrier where the operating temperature is below 
0°C. 

5.3.5 Stiffener angles, weld protrusions, ladder 
supports, insulation support rings, pipe hangers or any 
metal connections not otherwise scheduled to receive 
insulation shall be insulated, if in direct contact with 
the cold surface. The insulation over such protrusions 
shall have an insulation thickness over them of at least 



IS 14164 : 2008 



80 percent of the thickness of the adjoining insulation. 
In all such cases the insulation shall be extended to 
ensure that the nearest exposed surface has a 
temperature above 0°C or above dew point as specified 
by the purchaser. 

5.3.6 Wherever there is any discontinuity in vapour 
barrier in the vicinity of fittings or other protrusions 
on insulated cold surfaces, adequate vapour barrier 
shall be provided at such joints also. 

5.3.7 Vapour Sealing for Cold Insulation 

5.3.7.1 A cold insulation system is only as effective as 
its vapour barrier. A poor vapour barrier causes 
moisture migration into the body of the insulation 
causing the following: 

a) Deterioration in the insulation value, 

b) Physical damage to the insulation, and 

c) Corrosion of the insulated surface. 

5.3.7.2 Materials for vapour sealing 

The following materials are suitable for use as vapour 

seals: 

a) Foils — Aluminium foil, minimum 0.05 mm 
thick or foil laminated to kraft paper of 60 g/ 
m 2 , Min, or other suitable laminates sealed 
with bituminous or other adhesives. 

b) Bituminous and Resinous Mastics — Bitumen 
(conforming to fully blown type of IS 702 and 
its various compounds and resinous mastics 
having a water vapour permeance (for two 
coats) of not more than 2.8 x 10 3 g/s MN. 

c) Plastic Sheets — Mainly polyester, 
polyethylene, polyisobutylene and PVC 
coated fabric suitably sealed. Such sheets 
normally need further protection. 

5.3.8 Application for Vapour Seals 

5.3.8.1 When a vapour seal material is applied over 
insulation, it shall be carried down over all exposed 
edges of the insulation (for example, fittings on pipes 
or skirts on vessels) and bonded to the surface of the 
pipe or vessel. At all such points a mastic fillet shall be 
provided to round off the angle between the insulation 
and the cold surface. 

5.3.8.2 When insulating long runs of pipe, the ends of 
the insulation shall be sealed off at suitable intervals 
and the vapour seal shall be carried down to the pipe 
surface. 

5.3.9 In the case of cold insulation, the vapour seal 
and the protective finish of the main system shall have 
been completed before the insulation of the fittings is 
taken up. The main insulation shall stop short of the 
fittings on both the sides so as to allow for withdrawal 



of the bolts without disturbing the main insulation. In 
all cases, the vapour seal on the fittings shall be carried 
over to at least 50 mm beyond the finished vapour 
barrier of the main insulation system and sealed 
properly. The thickness of insulation applied to a fitting 
shall be atleast equal to the system on which the fitting 
is located. 

5.3.10 Vapour sealing materials shall be carried over 
expansion joints or contraction breaks without a joint. 

5.4 Insulation Supports 

5.4.1 The insulation shall be supported when applied 
to the sides of or underneath large vessels or ducts or 
to long runs of vertical piping. Supports shall be cleats, 
studs, washers, nuts, bolts, lugs, pins or collars (rings) 
which shall be either welded to the hot surface or to 
bands which are then strapped round the surface. These 
supports serve to hold the insulation in place, prevent 
its slipping, or support it above expansion joints. In 
addition, they shall provide necessary anchorage for 
lacing wire or wire netting which may be required to 
hold the insulation in place and/or to provide 
reinforcement for the insulation or a finishing material. 
Depending on their function, supports shall either 
penetrate only partly through the insulation or protrude 
slightly beyond it. But in no case the supports shall 
protrude through the final finish. 

5.4.2 Carbon steel lugs and attachments shall not be 
welded directly to alloy steels. Angles, flat cleats and 
similar large attachments may be secured by electric 
arc (welding) or gas welding, using a procedure 
appropriate to the materials, the thickness of the 
surface, and that of the attachment. For that surface on 
which site-welding of attachments is not permissible, 
it may be essential to pre-weld suitable metal pads to 
fix such attachments. 

The locations of studs or cleats will depend on the 
weight of insulation to be attached, as well as on the 
location of the surface, and on the degree of vibration 
to which the plant may be subjected under service 
conditions. For large flat surfaces, reasonable average 
spacing would be as given below: 

Vertical surfaces : 450 mm 2 spacing 

Upward-facing surfaces : 600 mm 2 or 750 

mm 2 spacing 
Over-hanging and down- : 300 mm 2 spacing 
ward-Facing surface 

For large-radius curved surfaces, if welding is 
permitted, 450 to 600 mm uniform spacing is 
considered suitable, but this may be modified for 
vertical large cylindrical surfaces when cleats are 
required to prevent downward movement of the 
insulating material. Cleats may not be required for 



IS 14164 : 2008 



horizontal cylindrical surface if it is possible to provide 
circumferential straps that can be tensioned over the 
insulation. 

Welded attachments should preferably penetrate into 
the insulating material only to the minimum extent 
necessary. In special circumstances, such penetration 
should not be > .7 times the thickness of the insulating 
material. The cross-sectional area of the attachments 
should be the minimum consistent with the required 
mechanical strength in order to avoid excessive transfer 
of heat (or cold) by metallic conduction. 

It is important to remember that a welded attachment 
will be subjected to the same extent of thermal 
movement as the insulation with the resultant 
possibility of tearing the insulation or finish, unless 
care is taken to allow for this, for example, by 
expansion joints or by use of ship lap joints. 

5.4.3 Insulation supports will depend on the insulation 
used, finish, mode of application and shall be adequate 
to prevent displacement of the insulation and its vapour 
barrier during operation. In no case shall the lugs or 
other insulation supports project over the cold surfaces 
for more than 0.70 times of the total insulation 
thickness, in order to avoid punctures in the vapour 
barrier. 

5.4.4 Insulation supports are normally provided after 
the final erection of plant. However, where for any 
reason whatsoever site welding is not permitted, the 
question of securing the insulation shall be considered 
at the design stage, so that provision for this purpose 
can be made while the equipment is being fabricated 
or erected. 

5.4.5 The purchaser shall indicate in his specification, 
the type of supports for insulation and cladding, which 
are to be supplied and fixed, and shall state whether 
welding will be allowed at site and on the surface to be 
insulated. 

5.5 Surface Preparation 

5.5.1 Before application of the insulation, the surface 
shall be wire-brushed to remove all dirt, rust, scale, 
oil, etc and dried. 

5.5.2 All surfaces shall be coated with a suitable anti- 
corrosive primer wherever necessary before they are 
insulated. Any shop-paint film has to be removed 
locally, down to the bare metal, before attachments are 
welded to the surface. Ideally, this paint would be 
applied after all welded attachments have been fixed 
in position. 

5.5.3 All austenitic stainless steel surfaces, proposed 
to be insulated and subjected to an operating 
temperature of 250°C and above shall be suitably 
protected by using inhibited insulating materials. 



5.6 Application of Insulation 

5.6.1 The method of Installation and securing of the 
insulating material shall be consistent with the 
requirements defined in 5.1, 5.2, 5.3, 5.4 and 5.5. The" 
following methods applicable to flexible insulation, 
rigid insulation etc, shall be followed. Further specific 
areas of work, namely, pipes, ducts, vessels etc, shall 
be insulated as given in 5.6.6. 

Stiffener angles, weld protrusions, ladder supports, 
insulation supports rings, pipe hangers or any metal 
connections not otherwise scheduled to receive 
insulation shall be insulated if there is an indirect 
contact with the hot surface. Thickness of insulation 
on such protrusions shall be not less than 50 percent 
of the thickness (t) of the main system. The minimum 
extension of the insulation over the protrusions from 
the main vessel or pipeline shall be equal to 4 t. 

5.6.2 Flexible Insulation 

Flexible materials, namely, mats, batts, or blankets 
faced on one or both sides with a suitable facing 
material, shall be applied in any of the following 
manner: 

a) By means of a tie wire (0.9 mm dia G.I.); 

b) By means of metal bands (for example 0.56 
mm thick, 20 mm wide); 

c) By means of wire netting on outer side, 
suitably laces; or 

d) By means of an adhesive between the layer 
and metal surface further assisted by a tie wire, 
if necessary. This is specially applicable for 
cold insulation. 

NOTES 

1 Unless otherwise specified, the diameter of lacing wire shall 
be 0.56 mm, Min and the wire netting shall be of maximum 
20 mm mesh and minimum 0.56 mm diameter. 

2 For interface temperature of 400°C and above, stainless steel 
binding wire/band/wire mesh shall be used. 

5.6.3 Preformed Insulation 

Rigid insulating materials, namely, blocks or boards 
may be applied in any of the following manner: 

a) By means of suitable metal bands (for 
example 0.56 mm thick, 20 mm wide); 

b) By means of wire netting on outer side; 

c) With edges lightly coated with an approved 
joint sealer, and further secured with metal 
bands (for example 0.56 mm thick, 20 mm 
wide) or tie wire (0.9 mm dia, G.I.); or 

d) By means of suitable adhesives, keeping in 
view the service temperature, with the joints 
duly sealed. 



IS 14164 : 2008 



NOTES 

1 Wherever preformed thermal insulating material is used, care 
shall be taken so that minimum numbers of segments are 
chosen. 

2 In all cases, care shall be taken to till the joints with the 
same basic insulating material in the loose form are properly 
packed into the joints. 

3 Effective vapour seal shall also be ensured while applying 
over cold surfaces. 

5.6.4 Plastic Composition Thermal Insulation 

5.6.4.1 These are supplied in the form of a dry powder, 
which is mixed with water to form a soft mortar of 
even consistency suitable for application by hand or 
with a trowel. 

5.6.4.2 Thermal insulating cements require heat for 
drying to ensure initial adhesion to the surface. All 
surfaces insulated with thermal insulating cements may, 
therefore, be kept warm throughout the application of 
the insulation. The temperature of the surface shall be 
as specified by the manufacturer of the cement. 

5.6.4.3 Initial adhesion between the insulation and the 
surface is best obtained by rubbing the surface with a 
handful of wet mortar. When this initial coat is dry, the 
first layer of insulation not more than 12 mm thick is 
applied by hand, the fingers being drawn through the 
material and pressed at the edges to ensure good 
adhesion. The surface shall be left rough and finger 
marked to form a good key for the next layer. 
Successive layers, each not more than 12 mm thick, 
shall then be applied in the same manner, until the 
required thickness is built up. Each layer shall be 
allowed to dry out completely before application of 
the next layer. The final layer only shall be trowelled 
to a smooth surface. Excessive troweling shall be 
avoided. 

5.6.4.4 On vessels, pipes and ducts, thermal insulating 
cements require reinforcement for thickness in excess 
of 40 mm. In such cases short lugs at suitable intervals 
shall be attached to the surface (see 5.4.1) to which 
are secured soft lugs of 2 mm diameter. These lugs 
wires shall be greater in length than the total thickness 
of the insulation. The insulation is then applied as 
prescribed in 5.6.4.3 but leaving the lugs protruding. 
When half the total thickness has cell applied and has 
dried out, the insulation shall be wrapped with soft 
wire netting 25 mm mesh and 0.56 mm diameter. This 
shall be laced together with soft lacing wire 0.56 mm 
diameter and fastened down to the lugs. When the final 
layer of insulation has been applied and trowelled 
smooth, and has dried out, a second layer of wire 
netting shall be wrapped around the insulation, laced 
together, and secured with the tie wires. The ends of 
the tie wires should then be pushed well into the 
insulation. 



5.6.5 Loose-Fill Insulation 

This may be adopted by agreement between the 
purchaser and the applicator. Locations where loose- 
fill insulation is recommended include the following: 

a) Expansion/contraction joints in an application 
when rigid insulation has been used, or 

b) Specific areas of the equipment where 
conventional methods of application may not 
be possible and where packing with loose fill 
is the only possible method of providing 
insulation. 

NOTE — The thermal insulation cement and loose-fill 
insulation are generally associated with insulation of hot 
surfaces and are not recommended for insulation of cold 
surfaces. 

5.6.6 Insulation of pipes, ducts, vessels, etc, shall be 
carried out by any one of the methods already 
mentioned. However, specific considerations 
pertaining to insulation of pipes, ducts, vessels etc, 
are detailed below in 5.6.6.1 to 5.6.6.3 subject to the 
precautions outlined in 5.1 to 5.5 above. Typical 
insulation of pipe at elevated temperature, pipe for 
cold application, pipe with elbow, bunch of tubes, and 
tank/equipment/vessels are shown as example in 
Fig. 1 to 7. 

5.6.6.1 Pipes 

On continuous runs of 6 m or more of vertical pipe, 
support rings shall be provided at not more than 3-m 
intervals. Such rings shall encircle the pipe and the 
radial lugs thereon shall have a length equal to 75 
percent of the total insulation thickness. 

5.6.6.2 Ducts 

When insulation is applied around the corners of the 
duct, care shall be taken to counteract the tendency of 
the material to thin down at these locations. 

5.6.6.3 Vessels 

All large vertical vessels of a height of 6 m or more 
shall be provided with support rings at not more than 
3 m intervals. Such rings shall encompass the vessel 
and the radial lugs thereon shall have a length equal to 
75 percent of the total insulation thickness. Extra 
insulation shall be provided over the support rings 
(see 5.1.4) This shall extend for 25 mm on each side 
of the ring and shall be mitred to 45°C for water-shed 
on the upper side. 

6 FINISHING 

6.1 Protective coverings or finishes are required over 
the insulation for one or more of the following reasons: 

a) Protection against mechanical damage, 



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IS 14164 : 2008 



b) Protection against weather or chemical attack, 

c) Retardation of flame spread, 

d) Appearance, 

e) Identification of pipe or vessel, and 

f) Providing the insulation with an easily cleaned 
surface. 

6.2 Protective Finishes 

The choice of the protective covering for thermal 
insulating materials can influence the choice of the 
insulating material itself. It is convenient to classify 
finishing materials under four broad types. 

6.2.1 Metal Sheet Materials 

Sheet materials of the types indicated in Table 1 are 
mainly recommended for plant, equipment and 
pipework. Metal sheet are widely used over both 
preformed and flexible insulating materials 
characterized by their resistance to mechanical damage 
and for their attractive appearance when correctly 
applied. 

External and internal corrosion is often a problem and 
for this reason aluminium and galvanized steel are 
preferred for majority of applications, provided that 
isolation from dissimilar metals is ensured. 

Profiled metal sheets give increased rigidity, while 
permitting lateral expansion movement. If there is a 
danger of condensation on the inner surface of the metal 
that is in direct contact with the insulating material, it 
is advisable to protect the contact surface with a suitable 
paint or a lamination of poly-coated paper/polymeric 
plastics compound before site application. 

6.2.2 Dry Mixtures 

Dry mixtures brought to paste consistency with water, 



for example, hard setting composition/Self-setting 
finishing cements are used mainly over preformed 
insulation on pipework and plant that can be heated 
for drying out. For spray-applied insulation, for 
example, over turbines in power stations, the finish 
invariably is self-setting cement; hard setting 
composition is used largely for the heating and 
ventilating applications. In all cases, some form of 
metal mesh reinforcement should be used and the final 
dry thickness should be sufficient to resist accidental 
mechanical damage. Sometimes it is possible to 
toughen the surface of a relatively friable hard-setting 
composition by embedding open-mesh woven textile 
fabric into the exposed surface. 

All the typical finishes of this group will absorb water, 
but may not disintegrate when wet. 

6.2.3 Solutions or Dispersion Coatings of Bituminous 
or Polymeric Plastics Origin 

Solutions or dispersion coatings of bituminous or 
polymeric plastics origin, which may vary in 
consistency from a heavily filled viscous mastic applied 
by trowel, to a mobile liquid applied by brush or spray 
gun. The products may be used for mechanical 
protection or for weatherproofing, or they may be self- 
coloured for colour-coding purposes over the finishes 
indicated in 6.2.2 above. 

Aqueous dispersions, on drying, tend to give films that 
are porous to water vapour (the so-called breather 
coats) whereas solutions in organic solvents tend to 
give dry films of low porosity. Application normally is 
by brush or spray gun. 

Thickness may vary according to the degree of 
protection required, but the final dry films for most 
normal coatings are likely to be about 1 mm or less. 
Mastics, which are heavy dough-like products of 



Table 1 Thickness of Metal Cladding 

(Clause 6.2.1) 



SI 
No. 



Type of Area 



(2) 



Protected Mild Steel 


Aluminium 


A 






A 


f 


^\ 


r 




Flat 


Ribbed 


Flat 


Ribbed 


mm 


mm 


mm 


mm 


(3) 


(4) 


(5) 


(6) 


1.2 


1.0 


1.2 


0.9 to 0.7 


1.0 


0.8 


1.2 


0.9 to 0.7 


1.6 





1.6 





As metal on 


— 


— 


— 


adjacent pipes 








1.0 


— 


1.2 


— 


0.8 


— 


0.9 


— 


0.6 


— 


0.7 


— 


1.6 


— 


1.6 


— 


1.0 





1.2 






i) Large Flat Area over flexible insulation 

ii) Smaller flat areas over flexible insulation or large areas over preformed slabs 

(including large curved surfaces) 
iii) Removable insulated manhole and door covers 
iv) Flange boxes and valve covers 

v) Pipes for more than 450 mm outside diameter over insulation 

vi) Pipes of more than 450 mm outside diameter over insulation 

vii) Pipes of less than 1 50 mm outside diameter over insulation 

viii) Recommended thickness for kicking plates 

ix) For flat surfaces, large curved areas and pipes of 450 mm or more outside 
diameter over insulation 

x) For pipes of less than 450 mm outside diameter over insulation 



16 



IS 14164 : 2008 



asphalt, bitumen, or polymeric plastics compounds, are 
used mainly as 'high-build' coatings, usually thicker 
than 1 mm. All of them may be reinforced with short 
mineral fibres to give increased durability. For heavy- 
duty weatherproofing the material preferably should 
be applied in two layers, with suitable open-mesh 
reinforcement, to give a final dry thickness of about 
3 to 5 mm. 

6.2.4 Flexible Sheet Materials of Organic Polymeric 
Compound 

Flexible sheet materials of organic polymeric 
compound, for example, high density polyethylene, 
flexible polyvinyl chloride or polypropylene, are of 
value when used as integral dry finishes over preformed 
pipe sections, in which case they may be secured to 
the outer surface of the insulating material by means 
of mechanical banding, welding or a suitable adhesive. 
Otherwise they may be applied as an outer covering 
for washability, in food/pharma industries. 

6.3 Ultimate Treatment of Finish Painting 

Pu'mi over the external finish of the insulation is not 
only of utilization value; as it is the painted surface 
that is exposed to view, the quality of the insulation 
work tends to be judged instinctively by the finished 
appearance. Correct choice and the correct methods 
of application should therefore receive adequately early 
consideration. For elevated surface temperature care 



S.S. BAND 



Rm 




should be taken to ensure that the paint used offers 
sufficient resistance to heat. 

7 FITTINGS 

7.1 The word fittings shall include valves, flanges, bends, 
stubs, end caps, bellows, expansion/contraction joints, 
venturies, orifice plates, elbows, reducers, tees, etc. 

7.2 Before the insulation of fittings is taken up, 
insulation of the pipe, with its protective finish, shall 
be completed. The insulation shall be stopped short of 
the fitting on both sides of the fittings so as to allow 
for the withdrawal of bolt without disturbing the 
insulation. 

7.3 The insulation of the fittings shall be carried out 
on the same as indicated in 5.6 above. Typical 
insulation of elbow, tee, flanges and valve are shown 
as example in Fig. 8 to 1 1. 

8 INSULATION OF EXPANSION JOINTS AND 
CONTRACTION JOINTS 

8.1 Depending upon the type of insulation used, the 
operating temperature and the nature of the plant, it 
may be necessary to provide expansion joints in hot 
insulation or contraction joints in cold insulation of 
vessels or pipes so as to prevent the insulation from 
rupturing or buckling when the hot or cold surface 
expands or contracts. Typical insulation of expansion 
joints are shown as example in Fig. 12. 




METAL SHEET. 

PREFABRICATED 

LOBSTAR BACK 



MATTRESSES 



DETAIL -A 

NOTES 

1 M.S. Rings shall be provided wherever required at suitable intervals as per sectional view. 

2 Metal cladding have 50 mm overlap longitudinally and circumferential joints will be sealed with sealing compound. 

3 Metal sheet cladding of specified thickness. 

4 In case of pipe section spacer ring not required. 

5 S.S. Band: 

a) Up to 0609 mm- 13 mm wide X 0.4 mm thick. 

b) Over 0609 mm -19 mm wide x 0.4 mm thick. 

6 In case of MOC IS S.S. a strip of 30 mm wide and 0.06 mm thick S.S. foil shall be provided wherever spacer ring lugs shall be 
setting. 

Fig. 8 Insulation of Elbow 



17 



IS 14164 : 2008 



nq 



METAL SHE ET 
CLADDING 




SS BAND 13MM WIDE, 



(0.9MM THK.) 

NOTES 

1 M.S. Rings shall be provided wherever required at suitable intervals as per sectional view. 

2 Metal cladding have 50 mm overlap longitudinally and circumferential joints will be sealed with sealing compound. 

3 Metal sheet cladding of specified thickness, 

4 In case of pipe section spacer ring not required. 

5 S.S. Band: 

a) Up to 0609 mm- 13 mm wide x 0.4 mm thick. 

b) Over 0609 mm- 19 mm wide x 0.4 mm thick. 

6 In case of MOC IS S.S. a strip of 30 mm wide and 0.06 mm thick S.S. foil shall be provided wherever spacer ring lugs shall be 



Fig. 9 Insulation of Tee 



SHACKLE LOCK 



INSULATION OF PIPE 




METAL SHEET 
CLADDING 

NOTES 

1 M.S. Rings shall be provided wherever required at suitable intervals as per sectional view. 

2 Metal cladding have 50 mm overlap longitudinally and circumferential joints will be sealed with sealing compound. 

3 In case of preformed rockwool pipe section spacer ring not required. 

4 S.S. Band: 

a) Up to 0609 mm -13 mm wide x 0.4 mm thick. 

b) Over 0609 mm -19 mm wide x 0.5 mm thick. 

5 In case of MOC IS S.S. a strip of 30 mm wide and 0.06 mm thick S.S. foil shall be provided wherever spacer ring lugs shall be 
setting. 

Fig. 10 Insulation of Flanges 



IS 14164 : 2008 



SHACKLE LOCK 



INSULATION 



VALVE 

SEALENT COMPOUND 




(SSBAND)13 MM WIDE , 
0.4MM THK . UP TO 609MM O.D. 



HEX, WIRENETT ING 
20MM MESH x0 0.7mm 



COMPOUND 




METAL SHEET, 

SECTIONAL VIEW 

NOTES 

1 M.S. Rings shall be provided wherever required at suitable intervals as per sectional view. 

2 Metal cladding have 50 mm overlap longitudinally and circumferential joint will be sealed with sealing compound. 

3 In case of preformed rockwool pipe section spacer ring not required, 

4 S.S. Band: 

a) Up to 0609 mm- 13 mm wide x 0.4 mm thick. 

b) Over 0609 mm- 19 mm wide x 0.5 mm thick. 

5 In case of MOC IS S.S. a strip of 30 mm wide and 0.06 mm thick S.S. foil shall be provided wherever spacer ring lugs shall be 
setting. 

Fig. 1 1 Valve Insulation 



EXPANSION JOINT* FILL 



METAL SHEET CLAD DING 
WITH OVERLAP OF 50MM 




NOTES 

1 M.S. Rings shall be provided wherever required at suitable intervals as per sectional view. 

2 Metal cladding have 50 mm overlap longitudinally and circumferential joint/will be sealed with sealing compound. 

3 In case of preformed rockwool pipe section spacer ring not required. 

4 S.S. Band: 

a) Up to 0609 mm - 1 3 mm wide x 0.4 mm thick. 

b) Over 0609 mm - 19 mm wide x 0.5 mm thick. 

5 In case of MOC IS S.S. a strip of 30 mm wide and 0.06 mm thick S.S. foil shall be provided wherever spacer ring lugs shall be setting. 



*In case expansion joint longitudinal overlap is without any groove for free movement of metal sheet. 

Fig. 12 Providing Expansion Joints 



19 



IS 14164 : 2008 



8.2 In all cases where supports rings are provided on 
vessels or vertical pipes for rigid materials, the 
insulation shall be stopped short about 5 mm from each 
ring, and the space between the insulation and the ring 
filled with a flexible insulation material. 

8.3 On horizontal pipes and vessels insulated with rigid 
insulation material or thermal insulating cements, 
expansion joints or contraction breaks filled with 
flexible insulating material shall be provided at suitable 
intervals. 

8.4 Flexible Thermal Insulations do not normally 
need expansion joints or contraction breaks. Mineral 
wool rigid sections used at temperatures not exceeding 
230°C also do not normally need expansion joints. 

8.5 Where sheet metal is used as the finish, the joints 
over the expansion joints or contraction break shall 
not be secured with screws or pop rivets. 

8.6 All other finishing materials shall be carried over 
expansion joints or contraction breaks without a joint. 

9 MEASUREMENTS 

9.1 General 

Insulation work consists of providing all materials 
required for the system which includes the required 
quantity of insulation material, support system for 
insulation and the cladding, finishing and other 
ancillary items like wire-netting, securing devices like 
bands, screws, etc, along with other needs like labour 
required for carrying out the task. 

While performing this work over each unit area of 
insulation work, certain overlaps, cutting wastage, etc, 
are involved, all of which are to be provided by the 
installer. Plane areas such as in ducts, Boiler walls, 
etc, are considered as Flat Surface where such extra 
material needs would be minimum. Actual work in field 
would consist of many different situations-curved 
surfaces like tanks, cylindrical vessels, domed/dished 
ends of such vessels, etc, which would involve larger 
elements of such efforts, apart from additional work 
with longer labour deployment, when compared to 
work on a flat surface. 

In cylindrical surfaces, although the inner perimeter 
may be less than the outer, the quantity of insulation 
materials required to carry out work would correspond 
to the larger perimeter — a block type/preformed 
material requiring cutting and shaping from the larger 
sized starting material, while a flexible material is taken 
to cover the larger perimeter and applied with higher 
and higher compression as we proceed towards the 
inner surface. Hence, all insulation work is measured 
on the larger (outer) surface. 



9.2 Measurement of Apparatuses (Insulated) 
Surfaces 

9.2.1 Basic parameter in work measurement considered 
being a flat surface, a set of diagrammatic presentations 
are furnished on various possible shapes which may be 
encountered in field, with the factors to be applied to 
account for extra materials for such items of work (see 
Fig. 13 to Fig. 26). The formulae for calculation of the 
conventional surfaces are indicated against each figure. 

The main symbols appearing in said figures/formula 
are the following: 

L,L\ = lengths relevant to straight parts of 

insulations included between the 
references defined, case by case, in 
the typical exemplifications, in m; 

C, C, = circumferences measured on the 

external surface of insulation, in m; 
X - conventional equivalent lengths of 

insulated parts having irregular 
shapes, in m; 

Y = increased coefficients of insulated 

parts having irregular shapes, in m; 
Z = height of the dished end; and 

D, D, = conventional external diameter of 

insulated apparatuses, in m, obtained 
by the following formula: 
D(or£>,) = D C + 2T 
where 

D e = external diameter of the apparatus, in m; and 

T = nominal thickness of insulating material 
provided by mechanical (finishing 
excluded), in m. 

9.2.2 Any mode of measurement other than the above 
may also be adopted, if agreed to between the purchaser 
and the applicator. 

9.3 Measurement of Piping Surfaces 

9.3.1 Insulated Piping Outside Diameter 

The outside diamefer of the insulated piping, to be taken 
into account when calculating the insulating surface, 
shall be the theoretical conventional diameter 
determined according to the following formulae: 



where 
D 

D, 



outside diameter of insulated piping, in mm; 

outside diameter of bare piping, in mm; 

outside diameter of tracing pipe, 
corresponding to 20 mm (conventional 
value), in mm; and 

thickness of insulation material provided by 
the design (finish excluded), in mm. 



20 



IS 14164 : 200U 



Typical Exemplifications 



Relevant Surfaces 



Fig. 13 




CL 



Fig. 14 




D 2 K 

CL+ —— Y 
4 



Y= 1.27 where Z<D/3 

and 
Y= 1.75 where Z> D/3 



Fig. 15 




d 2 n 
CL+— Y 



7= 1.27 where Z< D/3 

and 
K= 1.75 where Z> D/3 



21 



IS 14164 : 2008 



Typical Exemplifications 



Relevant Surfaces 



Fig. 16 




CL+ Y 

2 



r= 1.27 where Z<£>/3 

and 
Y= 1.75 where Z>D/3 



Fig. 17 




c + r 



c,x, + ^ 



y= 1 .2 and 
r, = 1.27 where Z<D/3 

and 
r, = 1.75 where Z>D/3 



22 



IS 14164 : 2008 



Typical Exemplifications 



Relevant Surfaces 



Fig. 18 




C(L + Xa + Xb+Xc) 
where 

Xa = 1 
AT5 = 0.5 
Xc = 0.5 



Fig. 19 




CL + C,(L I +Xa)+ — Y 



where 

Xa = 0.5 
Y = 1.27 where Z<£>/3 

and 
Y= 1.75 where Z>D/3 



Fig. 20 





C + C 
CL + - — s- tm.r 

2 

where 

r=i.2 



23 



IS 14164 : 2008 



Typical Exemplifications 



Relevant Surfaces 



Fig. 21 




2 

c,l, + °£y 



K= 1.27 where Z<D/3 and 
Y= 1.75 where Z>D/3 



Fig. 22 




CL + 



D 2 rt 



Fig. 23 




ForG>3m:CL + G 2 7t 
For G < 3 m 
CL + G 2 n.Y 
where K= 1.5 



24 



IS 14164 : 2008 



Typical Exemplifications 



Relevant Surfaces 



Fig. 24 






a + °±Y 

4 


Y= 


1.27 where Z<D/3 




and 


y+ 


1.75 where ZsD/3 



Fig. 25 




CL + ^Y 

4 



where Y= 1.27 



Fig. 26 




D 7T 



K= 1.27 where Z<£>/3 

and 
K= 1.75 where Z>£>/3 

and 
K, = 1 .2 



25 



IS 14164 : 2008 



9.3.1.1 Hot and cold insulation with sheet metal finish: 

D = Z) c + 2T 

9.3.1.2 Traced piping hot service insulation with sheet 
metal finish: 

D = D e + D t + IT 

NOTE — For areas having non-circular section (for example 
square section) the above formulae are still valid, considering 
D as equivalent diameter. 



£> = £> 



where 



D„. 



Perimeter of non-circular section, in mm 



9.3.2 Measurement of the Lengths Relevant to Insulated 
Piping 

9.3.2.1 Measurements shall be carried out in 
compliance with typical examples as per Fig. 27 for 
NB < 50 mm piping and Fig. 28 for NB > 50 mm 
piping. 

9.3.2.2 Pipe fittings 

Irregularly shaped insulation involving special 
execution procedure (like elbows, fittings, T-branches, 



etc) shall be converted to equivalent straight piping 
lengths, according to Table 2. 

9.3.3 Measurement criteria of L lengths relevant to 
NB < 50 mm piping is given in Fig. 27. 

9.3.4 Measurement criteria of L lengths relevant to 
NB > 50 mm piping is given in Fig. 28. 

9.3.5 Calculation of Surface to be Insulated 

9.3.5.1 Insulation of single piping 

The surfaces being insulated shall be conventionally 
determined as follows: 

A __ ftIA(L,+L ei ) 
1000 
where 

A = surface being insulated, in m 2 ; 

Di = outside diameter of insulated T piping, 

according to the definitions as per 9.3.1 in 

mm; 
X Li = summation of lengths of straight '/' piping 

lengths, m (see Fig. 27 and Fig. 28); and 
ZL ei = summation of conventional equivalent 

lengths Ljfor special parts relevant to W 

piping, m (see Fig. 28), in m. 



Table 2 Conventional Equivalent Lengths for Special Parts (1) 

(Clause 9.3.2.2) 



Piping 


Elbow 


Elbow 


Tee 


Reducer 21 


Cap 


Insulated 


Insulated 


Insulated 


Insulated 


Insulated 


NB 6 ' 


90E 


45E 


Branch 2 ' 3) 






Flange 
Pair with 
Remova- 
ble Box 4 ' 


Flanged 
Valve 
with 
Remova- 
ble Box 5) 


Flange 
Pair with 
Fix Box 4 ' 


Flanged 
Valve 

with Fix 
Box 5) 


Welded 
Valve 

with Fix 
Box 5 ' 




(M) 


(M) 


(M) 


(M) 


(M) 


(m) 


(M) 


(M) 


(M) 


(M) 


Hot and Cold Service Insulation with Sheet Metal Finish'* 


(1) 


(2) 


(3) 


(4) 


(5) 


(6) 


(7) 


(8) 


(9) 


(10) 


(II) 


<40 


0.5 


0.35 


0.70 


0.20 


0.20 


1.80 


2.50 


1.08 


1.50 


0.20 


> 50 to 85 


0.6 


0.40 


0.70 


0.20 


0.20 


1.90 


3.00 


1.14 


1.80 


0.60 


> 100 to 150 


1.00 


0.65 


0.70 


0.20 


0.20 


2.00 


3.50 


1.12 


2.10 


0.60 


> 200 to 350 


1.40 


0.85 


0.75 


0.20 


0.20 


2.50 


4.00 


1.50 


2.40 


0.60 


> 350 to 500 


1.50 


0.90 


0.85 


0.30 


0.20 


2.70 


4.50 


1.62 


2.70 


0.60 


>600 


1.70 


1.05 


1.10 


0.45 


0.20 


3.00 


6.00 


1.80 


3.00 


0.60 



NOTE — Radius of elbow is considered as 1 .5 D. 

" The equivalent lengths shown in the tables are applicable for types of insulation specified in same tables (these are the most 
frequently used insulation types); changing the application procedure of insulation (by eliminating, for example, the aluminium 
protection), the equivalent lengths might be different from the tabulated figures. 

-' For reducers and T-branches, the equivalent lengths refer to the higher NB. 

" Typical installations, such as pressure plugs, temperature plugs, vents, drains, etc, are not considered and calculated as '7* branches. 

41 Orifice fittings are conventionally considered as a pair of fittings. 

51 Flow meters, /-strainers, control valves, safety valves, sight glasses, expansion joints are conventionally considered as valves. 

61 For areas having non-circular section (see Note under 9.3.1.2). 



26 



IS 14164 : 2008 




Fig. 27 Measurement Criteria of l L' Lengths Relevant to NB < 50 mm 
Piping — Typical Example Equipment 



9.3.5.2 Bundle of piping insulated together is shown 
in Fig. 29. 

9.3.6 For protection of insulated pipelines, running 
close to the ground, from mechanical damage, due to 
foot traffic and/or from corrosion due to moisture from 
ground, any hardsetting compound and/or water 
proofing treatment is/are provided, such items of work 
are to be measured separately. 

9.3.7 Anti-corrosive painting or wrapping with 
aluminium foil over stainless steel/alloy steel piping 
and equipment prior to application of insulation shall 
be measured separately. 

9.3.8 Any mode of measurement other than the above 



may also be adopted, if agreed to between the purchaser 
and the applicator. 

10 INFORMATION REQUIRED 

10.1 The purchaser shall provide the contractor with 
the appropriate information under each of the following 
headings to enable the contractor to make a 
compressive offer/quotation. 

10.1.1 Application Specifications 

10.1.1.1 Selection of thermal insulating material 

Before deciding on the insulating material to be used 
for any specific purpose, the following factors should 
be considered: 



27 



IS 14164 : 2008 



Heat Insulation 

Cold-face temperature (minimum and maximum) 

Hot-face temperature (maximum and minimum) 

Ambient temperature 

Thermal conductivity 

Thickness of insulation required 

Mechanical strength 

Health hazard 

Fire hazard 

Thermal movement (expansion) 

Permeability of insulating material with need for 

protection 

Protective covering and finish 

Cost (including that for application and finish) 



Refrigeration 

Cold-face temperature (minimum and maximum) 

Warm-face temperature (maximum and minimum) 

Ambient temperature and humidity 

Thermal conductivity (aged) 

Thickness of insulation required 

Mechanical strength 

Health hazard 

Fire hazard 

Thermal movement (contraction) 

Vapour sealing of system 

Protective covering and finish 

Cost (including that for application and finish) 




Fig. 28 Measurement Criteria of 'L' Lengths Relevant to NB < 50 mm Piping — Typical Example 

28 



IS 14164 : 2008 




A=CL 



Fig. 29 Bundles of Pipes Insulated Together 



10.1.2 Types of insulation required for the main vessels, 
and pipes of each part of the plant and for bends, 
fittings, valves, hangers and other fittings. 

10.1.3 Type(s) ofFinish(es) Required 

10.1.4 If the thickness of the various insulations in 
the system are not furnished/or specified by the 
purchaser, then the basis of working out the different 
thicknesses shall be furnished by the purchaser, as 
for example, whether the thicknesses are to be 
calculated, based on: 

a) Economical thickness for a specified 
evaluation period; 

b) Specified heat loss or heat gain per unit 
dimension of the insulation; 

c) Specified temperature on outer surface of the 
insulation for personnel protection and safety; 

d) Prevention of condensation on the outer 
surface of the insulation. Outer surface 
temperature should be above the dew point; 

e) Specified temperature of the carried fluid 
along with maximum and minimum flow rates 
at the point of delivery; 

f) Any other specific requirement to be fulfilled 
by the thermal insulation; 



g) Velocity of the outside fluid (air); 
h) Material of the cladding surface; and 
j) Relative humidity. 

In each case, the purchaser shall provide the applicator 
with the requisite information as above, to enable the 
applicator to make the necessary calculations before 
making his offer/quotation. 

10.1.5 Details of the plant to be insulated including: 

a) Location: 

1) Indoors; 

2) Outdoors but protected; 

3) Outdoors exposed to weather; 

4) Ventilated or open trenches; and 

5) Difficult or unusual site conditions which 
will influence the selection of insulating 
and/or finishing materials, for example, 
in regard to transport, scaffolding or 
weather protection. 

b) Nature and material of construction of vessel 
and piping to be insulated. 

c) Dimensions of surfaces. If these are 
adequately detailed in drawings the provision 



29 



IS 14164 : 2008 



of copies shall suffice. Otherwise information 
of the following nature is required: 

1) Surface dimensions of vessels, 

2) External diameters and lengths of pipe 

3) Number and type of fittings, and 

4) Whether rotating or stationary. 

d) Temperature conditions including the normal 
and maximum working temperature of each 
portion of the plant and the ambient 
temperature to be reckoned for calculations. 

10.1.6 Special service requirements such as resistance 
to compression, in combustibility, abnormal variations 
or attack by solvents/corrosive media. 

11 TESTS 

11.1 Tests for Thickness 

Tests for thickness shall be carried out after application. 
Local irregularities (for example, rivet heads) on the 
insulated surface shall be ignored. 

11.1.1 If the arithmetic mean of not less than nine probe 
measurements at a given location is less than the 
minimum thickness as required by the purchaser or 
less than the commercial thickness offered by the 
applicator (subject to previously agreed tolerances), 
whichever is appropriate, the material applied at that 
location shall be deemed not to comply with this 
standard. 

11.2 Uniformity of Thickness 

11.2.1 Uniformity of thickness shall be assessed from 
the same measurements as in 11.1.1, if any 
measurement varies by more than ±13 mm or ±15 
percent whichever is appropriate, the material applied 
at that location shall be deemed not to comply with 
this standard. 

11.2.2 If thickness at any particular location is beyond 
±15 percent from the agreed thickness, the test shall 
be repeated at two more locations in the immediate 
vicinity of the first location. If both the tests are within 



15 percent from the agreed bulk density, the results 
shall be deemed to be satisfactory. However, if any of 
the two tests are beyond ±15 percent, the insulation 
shall be deemed to have failed in the bulk density test 
and the purchaser shall be at liberty to ask the supplier 
to redo the insulation in the required area. 

11.2.3 The test location shall be made good by the 
applicator at no extra cost to the satisfaction of the 
purchaser. 

11.3 Test for Bulk Density 

This test shall be optional and shall be resorted to only 
if previously agreed upon between the purchaser and 
the supplier. In such a case, the number of such tests 
for the whole work shall also be predetermined (see 
also 5.1.2). 

11.3.1 The test for bulk density shall be carried out 
after the measurements of thickness and area have been 
taken on the insulating material. 

11.3.2 The location where tests for bulk density are to 
be conducted shall be selected by the purchaser. 

11.3.3 If thickness at any particular location is 
beyond ±15 percent from the agreed thickness, the 
test shall be repeated at two more locations in the 
immediate vicinity of the first location. If both the 
tests are within 15 percent from the agreed bulk 
density, the results shall be deemed to be satisfactory. 
However, if any of the two tests are beyond ±15 
percent, the insulation shall be deemed to have failed 
in the bulk density test and the purchaser shall be at 
liberty to ask the supplier to redo the insulation in 
the required area. 

11.3.4 The test location shall be made good by the 
applicator at no extra cost to the satisfaction of the 
purchaser. 

11.4 Test for Finishing Cements 

The test for finishing cements shall be carried out after 
application and finishing of thermal insulation work 
and shall be done in accordance with the method 
prescribed in IS 9743. 



30 



IS 14164 : 2008 



ANNEX A 

(Foreword and Clause 3) 

SYMBOLS 



Symbol Title 

C, C, Circumferences measured on the external surface of insulation, defined case by 

case, in the typical exemplifications 

D, £>, Conventional external diameter of insulated apparatuses defined case by case, in 

the typical exemplifications 

Z)j Outside diameter of insulated V piping 

D e Outer diameter of bare pipe 

A Outside diameter of the tracing pipe 

d m Cylinder diameter to be taken as 0.6 for flat surface or diameter over 0.6 m 

d n Diameter of the outer surface of the nth layer 

T Nominal thickness of insulating material provided by mechanical (finishing 

excluded) 

A Surface area being insulated 

£ L-, Summation of lengths of straight 7 piping 

£ L ei Summation of conventional equivalent lengths U for special parts relevant to V 

Q Quantity of heat passing through a unit area of the pipe/equipment/wall during a 

unit time 

Q K Quantity of heat transfer by radiation 

Q Q Quantity of heat transfer by convection 

« c Heat transfer coefficient by convection 

h r Heat transfer coefficient by radiation 

4 Ambient temperature 

t s Temperature of cold face of pipe/equipment/wall or cladding surface 

t Temperature of hot face of pipe/equipment/wall 

/ Overall thickness of insulation 

/„ Thickness of the nth layer of insulation 

L,L\ Length of straight parts of pipe line defined case by case, in the typical 

exemplifications 

/„ Thickness of the nth layer of insulation 

K Thermal conductivity of insulation 

K n Thermal conductivity of the nth layer 

E Emissivity 

F External total heat transfer surface coefficient, F=h Q +h T 

Z, eff Effective length of pipe line 

V Air velocity 

X Conventional equivalent lengths of insulated parts having irregular shapes 

Y Applied coefficients of insulated parts having irregular shapes 
Z Height of the dished end 



Unit 

m 

m 

m 
m 
m 
m 
m 
m 

m 

m 

m 

kcal/m 2 .h 

kcal/m 2 .h 

kcal/m 2 .h 

kcal/m 2 .h °C 

kcal/m 2 .h °C 

°C 

°C 

°C 

m 

m 

m 

m 
mW/cm °C 
kcal/m 2 .h °C 

kcal/m 2 .h °C 

m 

m/s 

m 

m 



31 



IS 14164 : 2008 



ANNEX B 

(Foreword) 

METHOD OF CALCULATION OF HEAT LOSS/GAIN FOR INSULATION 



B-l Thermal conductivity is measured using standard 
test method. A series of measurements are generally 
made at different hot and cold face temperatures to get 
the values at different mean temperatures. From these 
experimentally determined values, it is necessary for 
the purpose of heat transfer calculation to deduce the 
conductivity at the combination of hot and cold face 
temperatures appertaining to each particular 
installation. To do this, the values are plotted against 
the corresponding mean temperature (the mean 
temperature being the arithmetic mean of the hot and 
cold face temperatures) and a smooth curve is drawn 
through the points. For any particular installation the 
appropriate Thermal conductivity value is then the 
value read from the graph for the mean temperature 
corresponding to the actual hot and cold face 
temperatures of that illumination. 

B-2 Where the conductivity values at the exact mean 
temperature are not available even by intrapolation/ 
extrapolation (if permissible) as given in relevant index, 
values for the nearest higher temperature may be 
accepted for design, the difference between desired and 
available temperature being not more than 50°C. 

NOTE — Normal conditions here mean broadly that the cold 
face of the insulation is, apart from any finishing materials, 
exposed to the atmosphere. It may, of course, reach a 
temperature well above atmospheric temperature. 

B-3 Design thickness of any insulation material for a 
particular use may be done according to the specific 
requirement of the user/purchaser according to the 
normal methods of calculations which are normally 
available. 

B-4 METHOD OF CALCULATION 

B-4.1 For Flat Wall 

Heat transfer through a flat wall, hearth, or roof 
consisting of V layers is given by the following 
equation. 

Q = (t — O/KZ./ff, + l 2 /K 2 + + IJKJ + UF] 

where 

F = h r + h c 

B-4.2 For Cylindrical Wall 

In case of a cylindrical wall calculate the quantity of 
heat passing through the insulation by the equation 
given below: 



i'o-ta) 



\{d n /2K,ln d x d e +d n l 2K 2 l nd 2 /d l 



+dJ2KJnd„/d n _ 1 ) + UF] 

Heat is transferred from the cold face of the wall in to 
open air through radiation and convection. Calculate 
the heat transferred through radiation and convection 
by the equation given below: 

Q = Q, + Q c = (K + h c ){t>-Q 

B-4.3 Radiation Heat Transfer Coefficient 

Calculate the radiation heat transfer Coefficient (/z r ) 
by the equation given below: 

h t = 4.876 x 10- 8 x e x {(r s + 273) 4 - (r a + 273) 4 }/(r s - r a ) 

B-4.4 Heat Transfer Coefficient for Convection 

Calculate the convection heat transfer co-efficient (h c ) 
by the equation given below: 

h c = 2.71 x 1.15 x 1/(39.37 x dj>- 2 x (0.55/f av )° 181 x 
(f s - f a ) - 266 x (1.8) 1266 x (196.85 V/68.9 + l) 05 

where 

Q = quantity of heat passing through a unit area 
of the pipe/equipment/wall during a unit 
time, in kcal/m 2 .h; 

Q r = quantity of heat transfer by radiation, in 
tfcal/m 2 .h; 

Q c = quantity of heat transfer by convection, in 
kcal/m 2 .h; 

d e = pipe outer diameter, in m; 

d x = diameter of the outer surface of the first 
layer, in m; 

d n = diameter of the outer surface of the nth layer, 
in m; 

t = temperature of hot face of pipe/equipment/ 
wall, in °C; 

t s = temperature of cold face of pipe/equipment/ 
wall or cladding surface, in °C; 

r a = ambient temperature, in °C; 

F - heat transfer co-efficient, in kcal/m 2 .h °C; 

h r = heat transfer co-efficient by radiation, in 
kcal/m 2 .h °C; 



32 



IS 14164 : 2008 



h c = heat transfer co-efficient by convection, in 
kcal/m 2 .h °C 

e = emissivity of the wall; 

K\ = thermal conductivity of the first layer, in 
kcal/m 2 .h °C; 

K 2 = thermal conductivity of the second layer, in 
kcal/m 2 .h °C; 

K n = thermal conductivity of the nth layer, in 
kcal/m 2 .h °C; 

/, = thickness of the first layer of insulation, in 
m; 

l 2 = thickness of the second layer of insulation, 
in m; 

/„ = thickness of the nth layer of insulation, in 
m; 

d m = cylinder diameter in meters, to be taken as 
0.6 for flat surface or diameter over 0.6 m; 

t w - average of surface temperature and ambient 
temperature, °K = [0.5 x (/ a + / s )] + 273.15; 
and 

V = air velocity, in m/s. 

NOTE — Thermal conductivity, k(kcal/m.h°C) used in this 
formula represents the value at mean temperature. 

B-4.5 Recommendation 

Temperature over insulated systems are parameters that 
are influenced by the heat flow from (or inch) system 
and the ambient factors like air temperature and air 
flow velocity over the surface. 

Apart from safety criteria from which they should be 
limited to 55°C, Max under all conditions of exposure, 
this parameter is the only easily measurable entity to 
determine heat loss/gain. 

Permissible heat losses differ from application to 
application. However, the following criteria are 
normally advisable: 



Operating 


Maximum 


Maximum 


Temperature 


Permissible 


Surface 


Range, °C 


Heat Loss, 


Temperature 




kcal/m 2 /h 


Differential 


<150 


50 


10 


150-250 


85 


17 


250-400 


100 


20 


400-550 


125 


25 



B-5 ADDITIONAL HEAT LOSSES DUE TO 
COMPONENTS IN A PIPE LINE 

For a realistic calculation of heat losses, the following 
modifications are required to be done: 

a) Valves and Slide Valves 

Additional length (A L), in metres, from the 



table below are to be added to the real length 
(L) of pipeline, to account for the presence of 
valves and slide valves in a piping system 
before calculating the heat loss. These values 
account for the valve and its own flanges, but 
not for the flanges where the valve mounts in 
the piping system. 

L eff = L + A L 

Values in the table assume typical industrial 
insulation thicknesses for the temperatures 
given, and thermal conductivities K = 0.8 
mW/(m.°C) at 100 C C mean temperature, and 
K = 1.0 mW/(m°C) at 400°C mean 
temperature. 



Pipe diameter d n in cm 


10.0 


50.0 


Pipe temperature, in °C 


100 


400 


100 


400 


Pipe Non-insulated valve 
located 2/3 Insulated valve 
inside 3/4 insulated valve 


6 
3.0 

2.5 


16 
6.0 
5.0 


9 

4.0 
3.0 


25 
10.0 
7.5 


Pipe Non-insulated valve 
located 2/3 Insulated valve 
outside 3/4 insulated valve 


15 
6.0 

4.5 


22 
8.0 
6.0 


19 
7.0 
6.0 


32 
11.0 

8.5 



b) Pair of Flanges 

To account for the heat losses from a pair of 
flanges in a piping system (including the 
flange pair when a valve is mounted): 

1) Non-insulated flanges: From the table 
above, use one third given for a valve of 
the same diameter. Add this to the real 
length of the piping before calculating the 
heat losses. 

2) Insulated with flange boxes: To the real 
length of the piping, add one metre for 
each flange with flange box, before 
calculating the heat losses. 

3) Insulated flanges: No adjustment 
required; calculate heat losses based on 
real length. 

c) Pipe Suspensions 

Add to heat loss calculation (without previous 
compensation for other components): 
In interior spaces : 15 percent of the heat loss 
In the open air : 20 percent of the heat loss 

without wind 
In the open air : 25 percent of the heat loss 

with wind 

d) Supports for Sheet — Metal Pipelines Jackets 
Additions to thermal conductivity: 

1) For steel supports : 0. 10 mW/cm°C 

2) For ceramic supports: 0.03 mW/cm°C 



33 



IS 14164 : 2008 



B-6 SURFACE TEMPERATURE AND SURFACE 
COEFFICIENTS 

B-6.1 It is often stipulated in practice, for operational 
reasons, that a certain surface temperature, temperature 
of the surface above that of the air (also called excess 
temperature) must not be exceeded. The surface 
temperature is no measure for the quality of the thermal 
insulation. This depends not only on the heat 
transmission but also on operating conditions, which 
cannot be readily determined or guaranteed by the 
manufacturer. These include among other things: 
Ambient temperature, movement of the air, state of 
the insulation surface, effect of adjacent bodies, 
meteorological conditions, etc. Reduction of heat loss 
by convection would mean reduction of air movement 
over the surface and consequent reduction of 
convective heat transfer surface coefficient. Reduction 
of heat transfer by radiation would mean reduction of 
surface emissivity and consequent reduction of 
radiative heat transfer surface coefficient. Although the 
increase in total surface resistance, which is reciprocal 
of the total surface coefficient will decrease the heat 
flow, but would increase the surface temperature to a 
considerably greater extent. 

B-6.2 It may, however, be mentioned that convective 
heat transfer to cooler and modiative heat transfer from 
hotter environment would work in opposite direction 
and will have a moderating effect on surface 
temperature. 

B-6.3 Although the surface temperature is not a 
parameter, which can serve as a guarantee because of 
the above reasons, it plays an important practical role 
for carrying out thermal insulation work. Mostly, the 
radiative and convective heat transfer from the surface 
introduces significant deviation. As a very rough guide, 
for comparison purposes, measurement of surface 
temperatures could be done, if black radiation shields 
are provided and still air conditions are created around 



the surfaces temperature measurement point. However, 
it may be stressed that actual surface temperature will 
be dependent on the prevailing exposure conditions. 
If surface temperature measurement are needed to be 
done for the purchaser, the above conditions may be 
agreed to by the applicator/supplier and the purchaser/ 
user. 

B-6.4 Since an accurate registration of all relevant 
parameters will be impossible, the calculation of the 
surface temperature and excess temperature are inexact 
and cannot be guaranteed. Although it includes the 
effect of the ambient temperature on the surface 
temperature it assumes that the heat transfer by 
convection and radiation can be covered by a total heat 
transfer coefficient whose magnitude must also be 
known. However, this condition is generally not 
fulfilled because the air temperature in the immediate 
vicinity of the surface, which determines the convective 
heat transfer, mostly departs essentially from the 
temperature of other surfaces with which the insulation 
surface is in radiative exchange. 

B-6.5 Many heat transfer calculations involve the use 
of total external surface heat transfer coefficient (E) 
which is defined as the heat transfer per square metre 
of surface/hour for 1 °C temperature difference between 
the surface and surroundings (mW/cm 2 °C). 

Combining the effects of radiation and convection. 

Surface E 

Aluminium, bright rolled 0.05 

Aluminium, oxidized 0.13 

Austenitic steel 0.15 

Aluminium — zinc smelt 0.18 

Galvanized sheet metal, blank 0.26 

Galvanized sheet metal, dusty 0.44 

Non-metallic surfaces 0.94 



34 



IS 14164 : 2008 



ANNEX C 

{Foreword) 

CONVERSION FACTORS 



C-l QUANTITY OF HEAT 



C-l.l The fundamental unit is the joule (J) or watt- 
second, but in this standard milliwatt-seconds (m W.s) 
= J x 10 3 is used for convenience. 





raW.S 


kcal 


Btu 


1 milliwatt-second 
(mW.s) 


1 


2.388 x 10" 7 


9.478 x 10" 7 


1 kilocalorie (kcal) 


4.187 x 10 6 


1 


3.968 


1 British thermal 
unit (Btu) 


1.055 x 10 6 


0.252 


1 



C-2 THICKNESS 





cm 


m 


in 


1 centimetre (cm) 


1 


0.01 


3.937 x 10"' 


1 inch (in) 


2.54 


0.025 4 


1 



C-3AREA 





cm 2 


m 2 

m 


ft 2 


1 square centimeter 
(cm 2 ) 


1 


1.0 x 10" 4 


1.076 x 10' 3 


1 square meter (m 2 ) 


1.0 x 10" 


1 


1.076 x 10 


1 square foot (ft 2 ) 


9.29 x io 2 


9.29 x 10" 2 


1 



C-4 THERMAL TRANSMISSION 

The fundamental unit is the mW which equals to J/s x 10 3 





mW 


kcal/h 


Btu/h 


1 milliwatt (mW) 


1 


8.590 x IO' 4 


3.41 x 10' 3 


1 kilocalorie/hour 
(kcal/h) 


1.163 x io 3 


1 


3.968 


1 British thermal unit/ 
hour (Btu/h) 


2.931 x 10 2 


2.52 x 10' 1 


1 



C-5 THERMAL CONDUCTIVITY 

The fundamental unit is milliwatt-seconds per square 
centimeter per second for 1 cm thickness and 1°C 



difference in temperature, abbreviated in its 
rationalized form as mW/cm°C. 





mW/cm °C 


kcal/m h °C 


Btu in/ft 2 h °F 


1 mW7cm°C 


1 


8.598 x io -2 


6.933 x 10' 1 


1 kcal/m h°C 


1.163 x 10 


1 


8.064 


1 Btu in/ft 2 h°F 


1.442 


1.24 x 10' 1 


1 



C-6 THERMAL CONDUCTANCE AND 
TRANSMITTANCE 

Surface Convection and Radiation Coefficient 





mW/cm 2 °C 


keal/m 2 .h °C 


Btu/ft 2 h °F 


1 mW/cm 2 °C 


1 


8.598 


1.761 


1 kcal/m 2 h °C 


1.163 x IO' 1 


1 


2.048 x 10' 1 


1 Btu in/ft 2 h°F 


5.678 x 10' 1 


4.882 


1 



C-7 HEAT LOSS 

The fundamental unit is milliwatt-seconds per square 
centimeter per second, abbreviated in its rationalized 
form as mW/cm 2 . 





mW/cm 2 


kcai/m 2 .h 


Btu/ft 2 h 


1 mW/cm 2 


1 


8.598 


3.17 


1 kcal/m 2 .h 


1.163 x 10' 1 


1 


3.691 x 10' 1 


1 Btu in/ft 2 h 


3.15 x 10' 1 


2.71 


1 



C-8 HEAT GAIN 

The fundamental unit is milliwatt-seconds per square 
centimeter per second abbreviated in its rationalized 
form as mW/cm 2 . 





mW/cm 2 


kcal/m 2 .h 


Btu/ft 2 h 


1 mW/cm 2 


1 


8.598 


3.17 


1 kcal/m 2 h 


1.263 x 10' 1 


1 


3.69 x 10' 1 


1 Btu//ft 2 h 


3.15 x 10'' 


2.71 


1 



35 



IS 14164 : 2008 



ANNEX D 

(Foreword) 

COMMITTEE COMPOSITION 

Thermal Insulation Sectional Committee, CHD 27 



Organization 
Central Building Research Institute, Roorkee 
Bakelite Hylam Limited, Secunderabad 

Bharat Heavy Electricals Ltd, Tiruchirappalli 

Central Building Research Institute, Roorkee 

Central Electricity Authority, Ministry of Power, New Delhi 
Central Institute of Plastics Engineering & Technology, Bhopal 

Department of Coal (Ministry of Energy), New Delhi 

Department of Industrial Policy & Promotion, Ministry of 
Industry, New Delhi 

Engineers India Limited, Gurgaon 

Hyderabad Industries Limited, Hyderabad 

Indian Oil Corporation Limited (R & P Division), New Delhi 
Indian Petrochemicals Corporation Limited, Mumbai 

Lloyd Insulation (India) Ltd, New Delhi 

MECON Limited Ranchi 

Minwool Rock Fibres Limited, Hyderabad 

National Design & Research Forum, Bangalore 
National Physical Laboratory, New Delhi 

National Thermal Power Corporation Limited, New Delhi 

Newkem Products Corporation, Mumbai 

Nuclear Power Corporation of India Ltd, Mumbai 

PIBCO Limited, New Delhi 

Projects & Development India Ltd, Sindri 

Punj Sons Pvt Limited, New Delhi 

Reliance Industries Limited, Mumbai 

Research, Designs and Standards Organization, Lucknow 

TCE Consulting Engineers Ltd, Chennai 



Representative(s) 

Prof K. Ganesh Babu (Chairman) 

Shri N. P. S. Shinh 

Shir S. Gulati (Alternate) 

Shri R. Sankaran 

Shri Ravindra Prakash (Alternate) 

Shri R. K. Srivastava 

Dr B. M. Suman (Alternate) 

Shri D. K. Gilhotra 

Dr S. C, Shit 

SHRI P. PoOMALAl (Alternate) 

Representative 

Shri N. C. Tiwari 

Shri S. K. Jain (Alternate) 

Shri P. P, Lahiri 

Shri R. Nanda (Alternate) 

Shri D. Trivedi 

Shri S. Jagadesh Waraiah (Alternate) 

Representative 

Shri Mihir Banerji 

Shri Niraj Dixit (Alternate) 

Shri N. Srinivas 

Shri C. P. Khanna (Alternate) 

Shri K. K. Mishra 

Shri R. K. Badruka 

Shri Neville D'Souza (Alternate) 

Representative 

Dr Hari Kishan 

Shri R. B. Saxena (Alternate) 

Shri R. K. Dixit 

Shri Jadav Datta (Alternate) 

Shri Nimish V. Sura 

Shri V. K. Suri (Alternate) 

Shri S. A. Bohra 

Shri S. K. Rastogi (Alternate) 

Shri T. Udaya Kumar 

Shri A. K. Sen (Alternate) 

Shri Kamalesh Karkun 

Dr S. P. S. Khalsa (Alternate) 

Shri R. P. Punj 

Shri Gaurav Punj (Alternate) 

Dr U. K. Saroop 

Kumari Rashmi Palande (Alternate) 

Shri D. R. Gupta 

Shri A. K. Chaudhuri (Alternate) 

Shri V. Sreenivasan 

Shri M. Sjndararajan (Alternate) 



36 



Organization 
U. P. Twiga Fibreglass Ltd, New Delhi 

BIS Directorate General 



IS 14164 : 2008 

Representalive(s) 

Shri Ajay Gupta 

Shri Rahul Sood (Alternate) 

Dr U. C. Srivastava, Scientist 'F' and Head (CHD) 
[Representing Director General (Ex-officio)] 



Member Secretary 

Shri N. K. Pal 

Scientist 'E' (CHD), BIS 



Thermal Insulation Material Subcommittee, CHD 27 : 5 

Lloyd Insulations (India) Limited, Mumbai 

Bakelite Hylam Limited, Secunderabad 



Bharat Heavy Electricals Ltd, Tiruchirappalli 
Central Building Research Institute, Roorke 

Central Electricity Authority, Ministry of Power, New Delhi 
Engineers India Limited, Gurgaon 

Hyderabad Industries Limited, Hyderabad 

Indian Oil Corporation Limited, New Delhi 

Kavemer Power Gas, Mumbai 

Lloyd Projects Private Limited, New Delhi 

MECON Limited, Ranchi 

Megha Insulations Private Limited, Bhavnagar 

Minwool Rock Fibres Limited, Hyderabad 

National Fire Service College, Nagpur 

NTPC, New Delhi 

Newkem Products Corporation, Mumbai 

Projects & Development India Ltd, Noida 

Punj Sons Private Limited, New Delhi 

Reliance Industries Limited, Mumbai 

Super Urethane Products Private Limited, New Delhi 

TCE Consulting Engineers Ltd, Chennai 

U.P. Twiga Fibreglass Ltd, New Delhi 



Shri N. Srinivas (Convener) 

Shri K. C. Sharma (Alternate) 

Shri N. P. S. Shinh 

Shri S. P. S. Shinh (Alternate) 

Shri R. Sankaran 

Shri Shri Kumar 

Dr B. M. Suman (Alternate) 

Shri D, K. Gilhotra 

Shri P. P. Lahiri 

Shri R. Nanda (Alternate) 

Shri D. Trivedi 

Shri S. Jagdesh Waraiah (Alternate) 

Shri Sovnath 

Representative. 

Shri Rakesh Saxena 

Shri Anil Vasudev (Alternate) 

Shri K. K. Mishra 

Shri H. V. Shah 

Shri R. K. Badruka 

Shri P. B. Mahesh (Alternate) 

Shri K. C. Wadhwa 

Representative 

Shri Nimish V. Sura 

Shri V. A. Sura (Alternate) 

Shri B. K. Jha 

Shri A. P. Sinha (Alternate) 

Shri R. P. Punj 

Shri Gaurav Punj (Alternate) 

Dr U. K. Saroop 

Kumari Rashmi Palande (Alternate) 

Shri Prem Chand 

Shri Sunil Iain (Alternate) 

Shri P. K. Rakshit 

Shri D. Padmanabha (Alternate) 

Shri Ajay Gupta 

Shri Rahul Sood (Alternate) 



37 



IS 14164 : 2008 



Panel for Establishing Y-Factors and Conventional Equivalent Lengths of Different Parts, 

CHD27:5:P1 



Organization 
Engineers India Limited, Gurgaon 

Central Electricity Authority, Ministry of Power, New Delhi 
Lloyd Insulation (India) Ltd, New Delhi 
NTPC, New Delhi 

Projects & Development India Ltd, Noida 
Bureau of Indian Standards, New Delhi 



Representative(s) 
Shri P. P. Lahiri {Convener) 
Shri D. K. Gilhotra 
Shrimati S. Bose 
Shri Rekesh Kumar 
Shri A. P. Sinha 
Shri N. K. Pal 



38 



Bureau of Indian Standards 

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harmonious development of the activities of standardization, marking and quality certification of goods 
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without the prior permission in writing of BIS. This does not preclude the free use, in the course of 
implementing the standard, of necessary details, such as symbols and sizes, type or grade designations. 
Enquiries relating to copyright be addressed to the Director (Publications), BIS. 

Review of Indian Standards 

Amendments are issued to standards as the need arises on the basis of comments. Standards are also reviewed 
periodically; a standard along with amendments is reaffirmed when such review indicates that no changes are 
needed; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standards 
should ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of 
'BIS Catalogue' and 'Standards : Monthly Additions' . 

This Indian Standard has been developed from Doc : No. CHD 27 (1352). 



Amendments Issued Since Publication 



Amend No. 



Date of Issue 



Text Affected 



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